静态调强与容积调强技术在胃癌术后放射治疗中的剂量学比较

A dosimetric comparison of intensity modulated and volumetric arc radiation therapy for gastric cancer

目的比较胃癌患者手术后静态调强放射治疗(IMRT)与容积调强放射治疗(VMAT)的剂量学差异,为临床应用提供参考。方法选取29例胃癌术后患者,每例患者分别制定5野IM-RT、7野IMRT、单弧VMAT和双弧VMAT四种治疗计划,评估靶区和危及器官的剂量分布情况。结果 DA-VMAT在靶区剂量均匀性、适形度和肾脏保护方面较优,但在肝脏保护上逊于5F-IMRT。结论综合考虑靶区适形度、剂量均匀性、治疗效率和对肾脏的保护,DA-VMAT在胃癌放射治疗中具有放射物理的优势。

Objective To compare radiotherapy plans for gastric cancer using IMRT and single and（or） double-arc VMAT techniques.Methods 29 patients were replanned by 5-filed IMRT,7-field IMRT, SA-VMAT and DA-VMAT.Dose-volume histogram（DVH） statistics were analyzed to compare treatment plans.Results The DA-VMAT plans are better than the other methods in terms of PTV dose and OARs except for the liver.For the liver,5F-IMRT showed a slight advantage in V30 and mean dose to normal liver over that in DA-VMAT.Conclusions DA-VMAT provided better tumor coverage compared with 5F-IMRT, 7F-IMRT and SA-VMAT but DA-VMAT had no advantage of liver protection over the 5F-IMRT.Further studies are needed to establish treatment outcome differences between the four technologies.